Abstract
In order to discuss the relationship between the heat generation by elongation and the breaking of multifilaments, the heating of nylon 66 multifilaments during drawing was measured with a thermographic apparatus. In a simple elongation, several filaments broke before allover breaking and those filament ends were thought to cause the chain breaking of neighbor filaments by collision and friction. The temperature of the filament ends was increased instantaneously because of contractions, and the generated heat conducted to the neighbor filaments. The left filaments were elongated and heated still more because of increased temperature and stress, and they broke at the peak temperature point. The temperature of the breaking point increased 29.5°C from the room temperature and the other points increased 12°C. In a loop elongation, the heat generation of the looped point was larger than others and the temperature increased 6.2°C at breaking. In a knot elongation, only the knotted point was heat generated and the temperature increased 10.5°C at breaking.
